ReDivia - Repositorio Digital de l'Instit Valencià d'Investigacions Agràries
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Analysis of two larval-pupal parasitoids (Hymenoptera, Braconidae) in the biological control of Ceratitis capitata (Wiedemann) in Spanish Mediterranean areas
Get PDFThe Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae), is
considered a key pest in fresh fruit and citrus production in the Mediterranean
Bassin. Nowadays, it is being studied the use of several ecological methods
against this pest in some Mediterranean countries (Spain, Morocco and Tunisia),
like the Sterile Insect Technique (SIT), the classical biological control (CBC) and
the search for native parasitoids. Two exotic larval-pupal parasitoids of fruit-flies
have been imported by the IVIA to Spain: Diachasmimorpha tryoni and D.
longicaudata. As it occurs in other countries, in Spain it is being studied the
combined use of the SIT and overflooding releases of parasitoids to combat Medfiy
populations. To achieve this, only one parasitoid species is usually mass reared
and released. Over the last two years we have been analyzing the competitiveness
of D. longicaudata and D. tryoni in order to choose the species to be used together
with the SIT for the integrated control of the Medfl
First Report on Almond in Europe of Bacterial Spot Disease of Stone Fruits Caused by Xanthomonas arboricola pv. pruni
No full textUso de la visión artificial en la estimación automática de la calidad de los arilos de granada
Get PDFLa visión artificial es una técnica que, desde hace unos años, se viene empleando habitualmente para la inspección automática de frutas y hortalizas. La programación previa de unos parámetros de calidad permite objetivar la inspección e independizarla de factores que afectan a la tradicional inspección manual como son el cansancio o la disparidad de criterios entre operadores. A la hora de diseñar un equipo para la inspección de fruta procesada empleando esta técnica, la fruta procesada presenta una serie de particularidades respecto de la fruta fresca debido a su difícil manejo, a la mayor fragilidad de producto, a que habitualmente
está mojado o húmedo, o a la elevada cantidad de producto que se requiere analizar. El centro de Agroingeniería del IVIA ha desarrollado en colaboración con una empresa del sector un prototipo para la inspección automática de arilos de granada mediante visión artificial. El prototipo incluye sistemas para la individualización y transporte del producto, inspección y separación de un producto. Los algoritmos de procesamiento de imágenes de arilos permiten determinar su posición y color en tiempo real para después clasificarlo hasta en cuatro categorías diferentes con un porcentaje de acierto cercano al 90%
Acta Horticulturae
No full textSome crops do not adapt to winter disinfestation because low temperatures reduce the evaporation capacity of fumigants and its spatial distribution can't be done with the desired uniformity, and remaining phytotoxic residues need more time to be eliminated. The most problematic case in Spanish farming is on strawberry mother plants crop in highland nurseries, where disinfestation before plantation is done with soil temperatures about 10 degrees C during application. Main problems are soil fungi and the presence of weeds in springtime and summer with the mother plants still developing. In a first season were studied three new formulations of 1,3-dichloropropene 55.2% + chloropicrin 30.3% at 50 g/m(2) furnished by Agroqu micos de Levante SA., (Agrocelhone NE); methyl bromide 50% + chloropicrin 50% at 40 g/m(2) and a non disinfested check. Application has been done by shank injection, as is usually done, on mid March and crop started beginning of May. On a second season the best adjuvant was compared added or not to a set of standard mixtures of 1,3-D 36.7% and Chloropicrin 52.8%; 1,3-D 55.2% and Chloropicrin 30.3% formulated for shank injection and with emulsifiers and compared to methyl bromide. On a third season, 100 plants per plot, produced in our second season mother plant experiment, were transplanted in a commercial field at Lucena (Huelva) in order to monitor the yield, vigour and healthy state along a standard crop. The first season results showed that there are no significant differences with respect to weed control among treatments except for the check. In check treatment weeds seize the whole plot and finally plants together with weeds were eliminated. Runner production was improved by the new formulation up to the level of methyl bromide. The new formulation showed a better control of weeds than the standard mixture. On the second season, emulsifiable formulation and special formulations gave better control of weeds. On the third season no differences among treatments were found on yield and healthiness even with the check, but diameter of rhizomes on MB and especial formulations with adjuvant were significantly higher than standard formulations
Taxonomic study of Marinomonas strains isolated from the seagrass Posidonia oceanica, with descriptions of Marinomonas balearica sp nov and Marinomonas pollencensis sp nov.
No full textNovel aerobic, Gram-negative bacteria with DNA G + C contents below 50 mol% were isolated from the culturable microbiota associated with the Mediterranean seagrass Posidonia oceanica. 16S rRNA gene sequence analyses revealed that they belong to the genus Marinomonas. Strain IVIA-Po-186 is a strain of the species Marinomonas mediterranea, showing 99.77% 16S rRNA gene sequence similarity with the type strain, MMB-1(T), and sharing all phenotypic characteristics studied. This is the first description of this species forming part of the microbiota of a marine plant. A second strain, designated IVIA-Po-101(T), was closely related to M. mediterranea based on phylogenetic studies. However, it differed in characteristics such as melanin synthesis and tyrosinase, laccase and antimicrobial activities. In addition, strain IVIA-Po-101(T) was auxotrophic and unable to use acetate. IVIA-Po-101(T) shared 97.86% 16S rRNA gene sequence similarity with M. mediterranea MMB-1(T), but the level of DNA-DNA relatedness between the two strains was only 10.3%. On the basis of these data, strain IVIA-Po-101(T) is considered to represent a novel species of the genus Marinomonas, for which the name Marinomonas balearica sp. nov. is proposed. The type strain is IVIA-Po-101(T) (=CECT 7378(T) =NCIMB 14432(T)). A third novel strain, IVIA-Po-185(T), was phylogenetically distant from all recognized Marinomonas species. It shared the highest 16S rRNA gene sequence similarity (97.4%) with the type strain of Marinomonas pontica, but the level of DNA-DNA relatedness between the two strains was only 14.5%. A differential chemotaxonomic marker of this strain in the genus Marinomonas is the presence of the fatty acid C(17:0) cyclo. Strain IVIA-Po-185(T) is thus considered to represent a second novel species of the genus, for which the name Marinomonas pollencensis sp. nov. is proposed. The type strain is IVIA-Po-185(T) (=CECT 7375(T) =NCIMB 14435(T)). An emended description of the genus Marinomonas is given based on the description of these two novel species, as well as other Marinomonas species described after the original description of the genus
Control of brown rot of stone fruits by brief heated water immersion treatments
No full textThe effectiveness of brief (30 or 60 s) immersion in water at 24, 50, 55, 60, 65, or 70 degrees C was evaluated for the control of brown rot, caused by Monilinia fructicola, on California-grown peaches, nectarines, and plums. Inoculated fruits were treated and either stored at 20 degrees C for 5 days or at 0 degrees C and 95% RH for 30 days followed by 5 days at 20 degrees C to simulate commercial marketing conditions. Immersion in water at 55 degrees C for 60 s or at 60 degrees C for 30 or 60 s significantly reduced both decay incidence and severity among the remaining wounds that developed the disease. Water temperatures of 65 degrees C or higher were phytotoxic and caused moderate to severe surface injuries. Immersion in water at 60 degrees C for 60 s was effective for plums and it reduced the incidence of brown rot from more than 80% among control fruit to less than 2%. In nectarines, this treatment reduced decay incidence from 100 to less than 5% on fruit stored at 20 degrees C and from 73 to 28% on cold-stored fruit. Therefore, brief immersion in heated water can be an effective approach to manage postharvest brown rot of stone fruits, especially for the organic fruit industry. (C) 2010 Elsevier Ltd. All rights reserved
Identification of genes associated with bud dormancy release in Prunus persica by suppression subtractive hybridization
No full textTo better understand the molecular and physiological mechanisms underlying maintenance and release of seasonal bud dormancy in perennial trees, we identified differentially expressed genes during dormancy progression in reproductive buds from peach (Prunus persica [L.] Batsch) by suppression subtractive hybridization (SSH) and microarray hybridization. Four SSH libraries were constructed, which were respectively enriched in cDNA highly expressed in dormant buds (named DR), in dormancy-released buds (RD) and in the cultivars with different chilling requirement, ‘Zincal 5’ (ZS) and ‘Springlady’ (SZ), sampled after dormancy release. About 2500 clones picked from the four libraries were loaded on a glass microarray. Hybridization of microarrays with the final products of SSH procedure was performed in order to validate the selected clones that were effectively enriched in their respective sample. Nearly 400 positive clones were sequenced, which corresponded to 101 different unigenes with diverse functional annotation. We obtained DAM4, 5 and 6 genes coding for MADS-box transcription factors previously related to growth cessation and terminal bud formation in the evergrowing mutant of peach. Several other cDNAs are similar to dormancy factors described in other species, and others have been related to bud dormancy for the first time in this study. Quantitative reverse transcription polymerase chain reaction analysis confirmed differential expression of cDNAs coding for a Zn-finger transcription factor, a GRAS-like regulator, a DNA-binding protein and proteins similar to forisome subunits involved in the reversible occlusion of sieve elements in Fabaceae, among others
Efficacy of phosphine as a fumigant against Rhynchophorus ferrugineus (Coleoptera: Curculionidae) in palms. Short communication.
No full textThe red palm weevil, Rhynchophorus ferrugineus (Olivier) (Coleoptera, Curculionidae), the major pest of palms in the Mediterranean, has mainly spread through movement of infested plants. The aim of this work was to determine the possibility of using aluminium phosphide in palms as a safe quarantine treatment against this pest. Laboratory tests were carried out on eggs, young and old larvae, pupae and adults of R. ferrugineus with different doses of Eurofume (R) and mortality was assessed. Fumigations of infested canary palms were carried out in a hermetic container and subsequently palms were carefully dissected and all R. ferrugineus specimens found, either dead or alive, were counted. Results suggest that a dose of 1.14 g aluminium phosphide m(-3) for 3 days is enough to kill all stages of R. ferrugineus in an infested palm tree. Provided that applied dose of aluminium phosphide is not phytotoxic for palms, this treatment could significantly reduce at low cost the enormous risks that palm imports suppose worldwide
Use of Cholesterol in Sperm Cryopreservation: Present Moment and Perspectives to Future
No full textContents Sperm cryosurvival rates are not optimal for most species. Therefore, new cryopreservation strategies are needed with the objective of increasing the number of surviving sperm and the quality of those sperm after thawing. Cholesterol plays important roles in many sperm functions, including effects on membrane properties. One of these effects is to stabilize membranes at low temperatures. Thus, species that produce sperm which possess high membrane cholesterol : phospholipid ratios are more resistant to cold shock than sperm with low cholesterol : phospholipid ratios. Therefore, increasing the cholesterol content of sperm membranes may be a strategy that can improve sperm quality after freeze-thawing. In this review, information is presented related to using cyclodextrins pre-loaded with cholesterol for cryopreserving sperm from different species. The topics discussed include both in vitro and in vivo assessments of sperm quality after cryopreservation, as well as how increasing sperm cholesterol content affects other sperm functions
Evolutionary Genomics of Staphylococcus aureus Reveals Insights into the Origin and Molecular Basis of Ruminant Host Adaptation
Get PDFhenotypic biotyping has traditionally been used to differentiate bacteria occupying distinct ecological niches such as host species. For example, the capacity of Staphylococcus aureus from sheep to coagulate ruminant plasma, reported over 60 years ago, led to the description of small ruminant and bovine S. aureus ecovars. The great majority of small ruminant isolates are represented by a single, widespread clonal complex (CC133) of S. aureus, but its evolutionary origin and the molecular basis for its host tropism remain unknown. Here, we provide evidence that the CC133 clone evolved as the result of a human to ruminant host jump followed by adaptive genome diversification. Comparative whole-genome sequencing revealed molecular evidence for host adaptation including gene decay and diversification of proteins involved in host–pathogen interactions. Importantly, several novel mobile genetic elements encoding virulence proteins with attenuated or enhanced activity in ruminants were widely distributed in CC133 isolates, suggesting a key role in its host-specific interactions. To investigate this further, we examined the activity of a novel staphylococcal pathogenicity island (SaPIov2) found in the great majority of CC133 isolates which encodes a variant of the chromosomally encoded von Willebrand-binding protein (vWbpSov2), previously demonstrated to have coagulase activity for human plasma. Remarkably, we discovered that SaPIov2 confers the ability to coagulate ruminant plasma suggesting an important role in ruminant disease pathogenesis and revealing the origin of a defining phenotype of the classical S. aureus biotyping scheme. Taken together, these data provide broad new insights into the origin and molecular basis of S. aureus ruminant host specificity